Spring suspension



1968 A. F. HICKMAN SPRING SUSPENSION 7 Sheeis-Sheet 1 Filed Nov. 5, 1966INVENTOR. C(ZZe/ i on 75 Md W ATTORNEYS.

Nov. 12,1968 A. F. HICKMAN SPRING SUSPENSION '7 Sheets-Sheet 2 FiledNov. 3, 1966 BY W j ATTORNEYS.

Nov. 12, 1968 A. F. HICKMAN SPRING SUSPENSION 7 Sheets-Sheet 3 FiledNov. 3, 1966 IN VENTOR. 0Z5??? 1 771203277072 (I Mei ATTORNEYS.

a bm QN NQ mN QW Wu P B mm A Nov. 12, 1968 A. F. HICKMAN 3,410,573

SPRING SUSPENSION Filed Nov. 3, 1966 '7 Sheets-Sheet 4 ATTORNEYS.

Nov. 12, 1968 A. F. HlCKMAN 3,410,573

SPRING SUSPENSION Filed NOV. 3, 1966 7 Sheets-Sheet 5 INVENTOR. Q5561?FHZ211 272 W r Md ATTORNEYS.

1963 A. F. HICKMAN SPRING SUSPENSION 7 Shets-Sheet 6 Filed Nov. 3, 1966INVENTOR. QZewZFflib?man BY j "PP ATTORNEYS.

Nov. 12, 1968 Filed Nov. 3, 1966 A F. HICKMAN SPRING SUSPENSION 7SheetsSheet 7 INVENTOR. Q5667? Ffii'cfimarz ATTORNEYS.

United States Patent Oflice 3,410,573 Patented Nov. 12, 1968 3,410,573SPRING SUSPENSION Albert F. Hickman, Eden, N.Y. 14057Continuation-impart of application Ser. No. 484,849, Sept. 3, 1965. Thisapplication Nov. 3, 1966, Ser- No. 591,899

16 Claims. (Cl. 280104.5)

ABSTRACT OF THE DISCLOSURE While not limited to any particular service,the suspension is shown as being a so-called independent wheelsuspension between a frame and one of its supporting wheels, the wheelrotatably supporting an aXle and the axle supporting the free end of afirst arm which is in turn fixed to a hub member or cross shaftjournalled on the frame. A second arm is fixed to and projects radiallyfrom the hub member and compressively bears against the end of aresilient rubber body connected to the frame, the second arm acting uponthe rubber body in direct compression to expand and contract the rubberbody laterally of the force of such compression to provide substantiallythe entire resiliency in supporting the frame upon the wheel.

This application is a continuation-in-part of my copending applicationfor Heavy Duty Vehicle Spring Suspension Ser. No. 484,849, filed Sept.3, 1965 now Patent No. 3,298,711 dated Jan. 17, 1967.

This invention relates to a heavy duty vehicle spring suspension, suchas for highway and off-the-road heavy duty service, and moreparticularly to such a heavy duty suspension in which each wheel iscapable of vertical movement independently of the other wheelssupporting the vehicle frame. For the purpose of the application thedesignation of a wheel is meant to include both a single tire wheel andalso a so-called dual tire wheel, that is, a wheel composed of two rimstructures bolted together, side-by-side and each having a rubber tire.The present invention can be adapted to single independent wheelssupporting opposite sides of the rear end of a heavy duty vehicle frame;a pair of independent wheels in tandem supporting each side of the rearend of such a vehicle frame; or a group of three or more independentwheels in tandem so supporting each side of the rear end of a vehicleframe. The present invention is more particularly directed to such asuspension in which the spring means interposed between and resilientlysupporting the vehicle frame on each wheel is in the form of one or moreresilient rubber blocks which are compressed to provide the resilientresistance, although features of the invention are not limited to theuse of such rubber blocks as the resilient support. The tandem wheelforms of the invention are further characterized by load transfer ateach side of the vehicle frame from one tandem wheel to another throughtheir individual rubber blocks so that these rubber blocks are additivein compression, in providing a resilient support for the vehicle frame.

In common with this earlier application, general objects of the presentinvention are to provide such a sus pension which is free from frictionbut is controlled by an increased resistance to motion in proportion tothe amplitude and velocity of vertical main frame movement; whichconsists of compact components which are arranged so as not to interferewith frame and wheel movement and in which the vertical moving parts arearranged inside and close to the wheels and provide high and widesupport for the vehicle frame on the stub axles with resulting increasedstability; which can have softer springs than those now on the marketfor equivalent duty and at the same time have greater sidesway controlthrough high and wide spring mountings; which can have many years andhundreds of thousands of miles of carefree operation; in whichsubstantially all suspension bearings, other than the wheel bearings,can be in the form of rubber bodies distorted to provide the requiredmovement and being free from friction and lubrication or other servicerequirements; which is light in weight, particularly in unsprung weight;which is low in both initial cost and upkeep; which renders auxiliarydevices for the control of sideway unnecessary; and in which periodicvibration of the suspension is dampened out.

An important specific object of the present invention is to provide suchan independent wheel suspension which is adapted for very heavy dutyhighway and off the road service and can be adapted to single wheelssupporting opposite sides of the vehicle frame or two, or three or moreindependent wheels in tandem at each side of the vehicle frame.

Another specific object of the invention is, in such tandem wheelsuspensions, to provide load transfer between or among the tandem wheelsat each side of the vehicle frame so that an excess load on any onewheel is transmitted to its companion tandem wheel or wheels on the sameside of the vehicle frame.

Another specific object of the invention is to provide such a tandemindependent wheel suspension in which the compressive action of theseveral rubber blocks of each group of tandem wheels on one side of thevehicle frame is cumulative so as to contribute jointly to a softer andlow frequency ride.

Another most important specific object of the present invention is toprovide such a suspension in which the majority of components form asingle wheel suspension, two tandem wheel suspension, and a three ormore tandem wheel suspension can all be made identical and haveidentical connections with one another and the vehicle frame, thevarious types of suspensions differing essentially in minor equalizingand self-steering connections where the invention is embodied in atandem wheel suspension or six wheel suspension.

Another important object of the invention is to provide, in a tandemwheel suspenion, a simple and effective means for rendering the wheelsself-steering so as to avoid tire scuff in steering the vehicle around acurve or into and out of traffic.

Other objects and advantages of the invention will be apparent from thefollowing description and drawings in which: FIG. 1 is a fragmentaryside elevational view of the rear end of the vehicle frame in theposition of carrying a normal load and supported at each side by a twotandem wheel suspension embodying the present invention, parts beingomitted for the purpose of clarity, this view being taken on line 11,FIG. 3. In this and other views the direction of movement of the vehicleis shown by a large overhead arrow. FIG. 2 is a fragmentary longitudinalsection thereof taken generally on line 22, FIG. 3. FIG. 3 is afragmentary top plan view of the rear end of the frame and two tandemwheel suspensions shown in FIGS. 1 and 2. FIGS. 4 and 5 are enlargedfragmentary vertical longitudinal sectional views taken on thecorrespondingly numbered lines, FIG. 3. FIG. 6 is an enlarged verticaltransverse section taken on line 6-6, FIGS. 3 and 4, parts being shownin elevation. FIG. 7 is a fragmentary transverse section taken generallyon line 77, FIG. 4, parts being shown in elevation. FIG. 8 is afragmentary top elevational view taken on line 88, FIG. 7. FIG. 9 is afurther enlarged generally upright section taken on line 99, FIG. 4, andshowing the rubber block compression spring shackle forming a principalfeature of the invention. FIG. is a fragmentary section, longitudinallyof the vehicle frame, taken generally on line lib-10, FIG. 9. FIG. 11 isa fragmentary side elevational view similar to FIG. 1 and illustrating amodified form of the invention in which the vehicle suspension at eachside is in the form of a three tandem wheel suspension. FIG. 12 is aview similar to FIG. 2 and illustrating the form of the invention shownin FIG. 11. FIG. 13 is a side elevational view similar to FIG. 1 andillustrating a modified form of the invention embodying an individualsuspension for each wheel. FIG. 14 is a view similar to FIG. 2illustrating the form of the invention shown in FIG. 13.

The vehicle frame, all figures The main frame of the vehicle can be ofany suitable construction and is shown as comprising a pair of mainlongitudinal side frame bars 26, these main longitudinal side frame bars26 being in the form of inwardly facing channels which are shown asstraight and parallel and connected at their rear ends by a cross barshown as being in the form of inwardly facing channel 27 and which canalso be connected by intermediate cross channel bars 28 as shown in FIG.14.

Two tandem axle suspension, FIGS. 1-10 As with the other forms of theinvention, the frame 25 is shown as supported by rubber tired wheels 30,these wheels being shown in the form of dual tire wheels, that is, pairsof rim structures bolted together side-by-side and each pair of rimstructures being journalled on a stub axle 31 in any suitable manner(not shown), these stub axles extending horizontally transversely of theline of movement of the vehicle and the stub axles 31 at opposite sidesof the vehicle being normally arranged axially in line with each otheras best shown in FIG. 3. Each stub axle is welded or otherwise fixed tothe end of an arm 32 which can be of any suitable form but is shown asbeing of rectangular tubular form in cross section with the stub axle 31extending through and being welded to its outboard end, as best shown inFIG. 3. The inboard end of each arm 32 is welded to a horizontal crossshaft 33. This cross shaft is in the form of round tubular cross shaftextending horizontally transversely of the line of movement of thevehicle frame and being arranged parallel with its stub axle 31 and theaxis of its wheel 30.

The outer end of each tubular cross shaft 33 is journalled in a bearing35 which is preferably in the form of a rubber bushed bearing. As bestshown in FIGS. 5 and 6, each of these bearings 35 is shown as comprisinga rubber bushing 36 surrounding and held in compressive relation withthe outboard end of its tubular cross shaft 33 by half bearing housings33 and 39, these half bearing housings being drawn into compressiverelation with each other by bolts 40. The ends of the rubber bushings 36project beyond the half bearing housings 38, 39 and abut againstabutment rings 41 welded to the companion cross shaft 33 as best shownin FIGS. 6 and 7. Each half bearing housing 39 is provided with ahorizontal plate 42 welded thereto and which is bolted, as by bolts 43,to the bottom plate 44 of a spacer block 45, one or more adjustmentshims 45 (left hand FIG. 6) being interposed be tween these plates 42,44, for alinement purposes. The top plate 48 of each spacer block 45 isbolted as by bolts 50 to the underside of a plate 51 welded to theoutboard end of a tubular cross bolster 52 formed by a pair of identicaltubes 53 of rectangular form in cross section arranged side-by-side andwelded to each other. Each tubular bolster 52 extends under both mainlongitudinal side bars 26 of the vehicle frame 25 and is secured at eachend to the corresponding main longitudinal side frame bar 26 by a framebracket 56. Each frame bracket comprises a vertical plate 58 secured inany suitable manner to the outside of each main longitudinal side framebar 26 and having a flange 59 underlying this main longitudinal sideframe bar 4 and overlaying the cross bolster 52 as best shown in FIGS.5-7.

The inner end of each tubular cross shaft 33 is connected to thecorresponding cross bolster 52 by a bearing 65 which is also preferablya rubber hushed bearing. As best shown in FIGS. 4 and 6, each bearing 65comprises a rubber bushing 66 surrounding and held in compressiverelation with the inner end of the corresponding tubular cross shaft 33by a pair of half bearing housings 68, 69, these half bearing housingsbeing drawn into compressive relation with the rubber bushing 66 bybolts 70. The opposite ends of each rubber bushing 66 protrudes beyondits half bearing housings 68 and 69 and abut against abutment rings 71welded to the inner end of the cross shaft 33 in spaced relation to eachother. The half bearing housing 68 is provided with a cross plate 72suitably welded thereto.

This half bearing housing 68 for the front cross shaft 33 is secured tothe corresponding cross bolster 52 as follows:

The numeral 75 represents a horizontal plate welded to the underside ofthe front bolster 52 above each of the bearings 65 for the front axle33. This plate 75 is provided with front and rear downwardly projectingflanges 76 each of which carries an adjusting screw 78 extending througha threaded hole 77 in its flange 76 lengthwise of the line of travel ofthe vehicle. Each screw 78 carries a lock nut 79 to hold it in anyadjusted position. These adjusting screws 78 abut against opposite sidesof a structure comprising an upper plate 80 having slots (not shown)through which is attached by bolts 81 to the corresponding fr-arne plate75, a bottom plate 82 resting on and secured by bolts 83 to the crossplate 72 of the corresponding half bearing housing 68 and verticalplates 84 connecting these plates 80, 82 and extending lengthwise of thecross shafts 33 to provide abutments for the adjusting screws 76.

The upper half bearing 65 for the rear cross shaft 33 is secured to theframe 25 as follows:

The numeral 85 represents a horizontal plate welded to the underside ofthe bolster 52 above each of the bearings 65 for the rear cross rods 33.To each plate 85 is secured, as by bolts 86, a metal plate 87 whichforms the top wall of a rectangular oil box 88 filled with oil 89 asshown in FIG. 6. As best shown in FIG. 4, the fore-and-aft edges of thebottom plate 90 are of reversely formed or horizontal channel shape incross section, the channels 91 opening toward each other. This bottomplate 90 for the bearing 65 for each rear cross shaft 33 is preferablymade of graphite impregnated bronze and slidingly rests upon a hardsteel plate 92, the fore-and-aft edges of which are arranged in thechannels 91 so that when the frame 25 is jacked up to cause the rearwheels 30 to leave the ground, the rear wheel bearings 65 will beprevented from falling free from the slide bearing plates 90. Thefore-and-aft edges of the plate 72 for each rear half bearing housing 68also preferably project into these opposing channels 91. Desirably awick 93 meters the oil 89 from the interior of the oil box 88 through ahole 94 in the graphite impregnated bronze plate 90 to the top face ofthe hard steel plate 92 on which it slidingly bears. Each wick 93 alsoacts, through capillarity, to feed the oil 89 upwardly as is requiredfor the three tandem wheel suspension shown in FIGS. 11 and 12. Thesesliding bearing plates 90, 92 permits fore-and-aft movement of the innerend of each rear cross shaft 33 to render the rear tandem wheels 30selfsteering, as hereinafter described.

In the two tandem Wheel suspension shown in FIGS. 1-10, at compensatingarm, indicated generally at 95, is secured to the inner end of each ofthe cross shafts 33, these compensating arms extending generallyhorizontally in the direction of the line of movement of the vehicletoward a companion compensating lever 95 of the other cross shaft 33,and the outboard ends of these compensating levers are connected to eachother by a shackle 96 which provides substantially the entire resilientresistance between the vehicle frame 25 and the wheels 30. Thesecompensating arms are shown as constructed as follows:

Each compensating lever 95 comprises a pair of side plates 98 severallyprovided with openings by means of which they are fitted around andwelded to the inner end of the corresponding cross shaft 33, these sideplates being fitted against the corresponding abutment rings 71 so thatthese side plates 98 are arranged on opposite sides of the companionbearing 65. The outboard ends of each pair of side plates 98 areconnected together by a cross plate 100 connecting longitudinal edgesthereof and cross plates 101, 102 extending perpendicularly from thefore-and-aft edges of the companion plate 100 and bridging the spacebetween the pair of side plates 98. Preferably these plates 100, 101,102 for each compensating arm of the front cross shafts 33 form anupwardly opening pocket 104 whereas these plates for each compensatingarm 95 for the rear cross shafts 33 form a downwardly opening pocket105.

In each of these pockets is arranged a rubber block 108 which isvulcanized to a plate 109 secured, as by rivets 110 to the companionplate 100. On the side remote from the anchoring face of its plate 109each rubber block 108 is shown as being of frusto-conieal form, asindicated at 111, the body portion 112 of the rubber block 108 being ofhorizontally elongated rounding form.

A metal compression plate or cup 113 is held in pressure contact withthe conical end 111 of each rubber block 108. Each of these cups 113comprises a flat central portion 114 bearing against the flat end of itsrubber block 108; a frusto-conical portion 115, and an annular flange116 projecting outwardly generally parallel with the flat portion 114.The flare of the frusto-conical portion 115 of each compression plate orerr; 113 is preferably more divergent than the frusto-conical portion111 of its rubber block 108 so that a space 118 is left between thesefrustoconical portions to permit expansion of the rubber block 108 inpermitting vertical movement of the frame 25 relative to the road.

A semicircular channel bar 119, extending horizontally transversely ofthe line of movement of the vehicle, is welded at its center, asindicated at 120, to the exterior of the flat portion 114 of eachcompression plate or cup 113. In rolling contact with the salient Sideof each of these semicircular bars 119 is the concavity of anothersemicircular channel bar 121, these bars preferably being held againstdisplacement with reference to each other, other than through rollingcontact, by a pair of pins 122 welded to the bars 121 and projectinginto openings 123 in the salient side of each bar 119. It will be seenthat each bar 121 provides a rolling socket joint for its bar 119. Thecross bars 121 for each shackle 96 are connected together by shacklelinks 125. For this purpose one end of each of these links 125 iswelded, as indicated at 126, to the corresponding end of one cross bar121 and extends through openings 128 in the companion pair of plates 100to alongside the other cross bar 121. This other cross bar 121 isprovided with perpendicular end flanges 129 by means of which it issecured, by bolts 130, to the corresponding links 125.

Each shackle 96 also includes a rebound rubber block 131 compressedbetween the plates 100 of the companion pair of compensating arms 95 andpreferably secured to one of these plates by means of a metal base disk132 to which it is vulcanized.

Operation FIGS. 1-10 The direction of movement of the vehicle is shownby the large arrows above FIGS. 15 and in the operation of the form ofthe invention illustrated in FIGS. 1-10 the upward movement of one, say,of the front wheel stub axles 31 effects corresponding upward movementof its arm 32 and counterclockwise movement of the tubular cross shaft33 forming the hub of this arm, such movement being permitted by therubber bushings 36 and 66 of the bearings 35 and 65, respectively, whichare located at such points as to prevent cantilever or corner loading ofthese bearings. Each bearing 35 is located, for this purpose to be atleast in part outside of the plane of the inner circular face of theinside tire 30 and preferably, as shown, in line with its wheels 30, asbest shown in FIG. 3. Each inner bearing 65 is located, for thispurpose, within the area directly below the center part of the vehicleframe 25 so as to prevent corner loading of these bearings 35 and 65. Itwill therefore be seen that the T-arm support for each wheel, providedby the tubular cross shaft 33 and the arm 32 welded thereto, providesstability, the bearings 35, 36 being spaced wide enough apart to providea stable support for the corresponding stub axle 31 and also being solocated as to prevent cantilever or corner loading of these bearings.

The angular counterclockwise movement of the tubular cross shaft 33 ofthe assumed front wheel 30 at one side of the vehicle is transmitteddirectly to the compensating lever fixed thereto, this lever beingcomposed of the pair of side plates 98 welded to each cross shaft 33 onopposite sides of its bearing 65 as best shown in FIGS. 4, 6 and 7.Hence this angular movement of the front wheel cross shaft 33 causes anupward angular movement of its compensating lever 95 thereby, throughthe corresponding shackle 96, effecting an upward angular movement ofthe companion compensating lever 95 associated with the companion reartandem wheel 30. This angular movement of the compensating lever 95 forthe rear wheel 30 is transmitted directly to the rear tubular crossshaft 33 welded thereto. This imposes a corresponding downward movementof the assumed rear wheel compensating lever 95 and the stub axle 31 ofthe rear dual-tire tandem wheel 30 thereby to provide load transfer,that is, equalized loading between each pair of front and rear dual-tiretandem wheels 30 at each side of the vehicle.

It will be particularly noted that this load transfer from one to theother of the wheels 30 at each side of the vehicle is transmittedcompressively through the two resilient rubber blocks 108 forming partof the companion shackle 96, these rubber blocks forming substantiallythe entire resilient support for the frame 25 on the wheels. Thus, thedownward pressure of the upper compression plate or cup 113 serves tocompress and distort the upper frusto-conical portion 111 of the upperrubber block 108 into the divergent space 118 between it and thefrustoconical part of the compression plate or cup. Similarly the upwardpressure of the bottom compression plate or cup 113 serves first todistort or spread the frusto-conical portion 111 of the bottom rubberblock 108 into the surrounding space 118 provided by the greater flareof its compression plate or cup 113. This distortion is effected bycomparatively light forces from the wheels in driving overirregularities in the road, especially when unloaded, so that thefrusto-conical portions 111 provide a variable rate spring, that is, onewhich becomes more resistive as greater loads are impressed thereon andas the frusto-conical portions 111 of the rubber blocks distort toprogressively fill the compression plates or cups 113. Obviously therelative shape of the ends 111 of the rubber blocks 108 in relation tothe shapes of the interior portions of the compression plates or cups113 can be designed to provide any desired kind of variation in thespring rate under varying loads, the frusto-conical shape being selectedas exemplary.

Under heavy forces, the downward pressure of the top compression plateor cup 113 in opposition to the upward pressure of the bottomcompression plate or cup 113 serves to completely fill these cups and tocompress the cylindrical portions 112 of these rubber blocks. Theseportions 112, of course, distort radially under such heavy forces butdue to their size eliminate the need for bottoming stops since any forceencountered is incapable of flattening these cylindrical portions 112into wafer form.

Under rebound action, the rubber blocks 108 are incapable of separatingfrom operative contact with the insides of their compression plates orcups 113 by virtue of the small rebound rubber block 131 interposedbetween the opposing faces of the flat end plates 100 of the twocompensating arms 95, these rubber blocks 131 serving to hold theshackles 96 under pressure, against rattling or displacement of parts,at all times. It will particularly be noted that each rubber reboundblock 131 serves to hold the semicircular channel bars 119 in rollingcontact with the inside of the semicircular channel bars 121 connectedby the shackle links 125 so that these bars merely have rolling orrocking contact with one another and cannot jump apart and create anoisy condition. It will also be noted that the pins 122 preventrelative longitudinal movement of these bars 119, 121 so as to maintainthe cups 113 in axial alinement with both the rubber blocks 108 as wellas the interposed rebound rubber block 131.

An important feature of the tandem wheel suspension of FIGS. 1-10 isthat it is self-steering, that is, in rounding a curve, the spindles 31of the rear tandem wheels 30 will assume such angles in a horizontalplane, with reference to the spindles 31 of the front tandem wheels 30,as will enable all of the wheels to round the curve without tirescufiing. This self-steering is effected by the flat sliding bearingplates 90, 92 interposed between the inner bearings 65 for the reartandem wheels 30 and the frame 25 so as to permit limited fore-and-aftmovement of the inner ends of the rear cross shafts 33. Thus, referringto FIG. 3, in rounding a curve, say, to the right, the rear pair oftandem wheels 30 will be drawn to the right (with reference to the frame25), by the swinging of the rear end of the frame 25 to the left,through their frictional engagement with the roadway, in order to avoidtire scufling in rounding the curve. If this were resisted, tirescuffing would take place, but such movement of the rear tandem wheelsis permitted, the rear tandem wheels spindle arms 32, cross shafts 33and bearings 65 swinging counterclockwise about vertical axesintersecting the bearings 35 to permit the rear tandem wheels 30 totrack properly around the curve without tire scuff. This movement ispermitted by the sliding engagement between the graphite impregnatedbearing plate 90 on the hard steel plate 92, the movement of the formerpermitting the required forward movement of the inner end of the lefthand cross shaft 33 and the required rearward movement of the inner endof the right hand cross shaft 33 for this purpose. n returning to astraightaway, the rear pair of rubber tired wheels 30, again to avoidtire scuff, return to their normal coaxial relation shown.

It will be seen that each pair of rubber bodies 108 are acted upon indirect compression from their opposite top and bottom extremitiesgenerally along a center line of the path of movement of the outbardextremity of their lever 95 and that these bodies expand toward and fromthis center line to provide substantially the entire resilientresistance in supporting the frame 25 On the corresponding wheel 30.

Three tandem wheel suspension, FIGS. 11 and 12 All of the parts used toprovide the two tandem wheel suspension shown in FIGS. 110 are used inproducing the three tandem wheel suspension shown in FIGS. 16 and 17 andhence the same reference numerals have been used and a description oftheir construction and mounting will not be repeated. This three tandemwheel suspension is distinguished, however, both by a different formofcompensating lever 134 connecting the suspension for each of thecenter dual-wheels 30 with the suspension for the companion front andrear dual-wheels 30 so as to effect load equalization among all of thetandem wheels at each side of the vehicle, and also by a'diiferent formof resilient mounting for the inner end of each front tubular crossshaft 33 to effect self-steering of the vehicle.

This compensating lever 134 is double-ended or in the form of a walkingbeam, the forward end lever of which is indicated at 135 and the rearend lever of which is indicated at 136. Each end lever of this Walkingbeam 134 can be of the same construction as the compensating levers 95and is journalled on the frame 25 by means of a frame bearing identicalto the frame bearings 35 and 65, including the adjusting mechanism -84for the bearing '65 illustrated at the left of FIG. 4 and in FIG. 8. Therear end lever 136 of each walking beam 134 is connected by a shackle 96to the forward end of the equalizing lever 95 of the correspondingrearmost tandem wheel 30. The forward end lever 135 of this walking beamis connected by a shackle 96 to the rear end of the equalizing lever 95of the foremost wheel 30. The cross shaft 33 of the foremost wheel 30can be connected to the outer end of the bolster 55 by a rubber bushedbearing 35 in the same manner as with the form of the invention shown inFIGS. l-lO. However, with this particular foremost cross shaft 33, it isimportant that the horizontal bearing plates 90, 92 by means of whichself-steering and automatic self-alinement of the multiple wheelsuspension is achieved, be arranged under the corresponding bearing 65at the inner end of its tubular cross shaft 33 instead of above thetubular cross shaft as illustrated in FIGS. 4 and 6. To this end a frameplate 140 is secured, as by welding, to the underside of the foremostbolster 52 above each of the bearings 65, this frame bracket extendingforwardly and rearwardly from this bolster. A U-shaped bracket 141 hasits upstanding arms 142 embracing and fixed to the front and rear sideof this frame plate 140 with its cross part 143 arranged below the innerend of the cross shaft 33 as best shown at the left of FIG. 12. On thiscross part 143 is fixed, in any suitable manner, and inverted ascompared with FIGS. 1l0, a rectangular oil box 88, the top plate ofwhich is of graphite impregnated bronze. This bronze plate slidinglysupports a hard steel plate 92. This hard steel plate 92 has itsfore-and-aft edges arranged in the channels 91 provided at the front andrear of the bronze plate 90 and is suitably secured to the underside ofthe corresponding half bearing housing 69 to slidingly support thecorresponding bearing 65.

In operation of the three tandem wheel form of the invention illustratedin FIGS. 11 and 12, the upward movement of, say, the foremost wheel 30at one side of the vehicle effects upward movement of its stub axle 31to effect corresponding angular upward movement of its arm 32 and itstubular cross shaft 33, such movement being permitted by the rubberbushings 36 and 66 of the bearings 35 and 65, respectively. Thisrotation of the tubular cross shaft of the assumed foremost wheel 30 atone side of the vehicle is transmitted directly to the compensatinglever fixed thereto, and hence causes, through the corresponding shackle96, an upward angular movement of the forward end of the double endedlever or walking beam 134.

This walking beam is fixed to its central cross shaft 33 in turnjournalled in its frame bearings 35 and 65, the latter being preferablyadjustable lengthwise of the frame by screws 78 in the same manner aswith the front cross shaft 33 with the form of the invention shown inFIGS. 110.

The downward movement of the forward end 135 of the double ended leveror walking beam 134 also effects upward movement of the rear end 136thereof and hence, through the corresponding shackle 96, upward movementof the compensating lever 95 fixed to the rearmost cross shaft 33. Thisimposes, through the corresponding arm 32, downward pressure on the stubaxle 31 of the rearmost wheel 30. This downward force imposed upon thearms 32 and stub axles 31 of the center and rearmost wheels 30distributes the assumed load imposed on the foremost wheel 30 to thesecenter and rearmost wheels so as to effect load distribution among them.With the form of the invention shown in FIGS. 11 and 12 the shackles 96are of the form illustrated in detail in FIGS. 9 and and hence this loadtransfer is through the resilient rubber blocks 108 in compression andwhich serves to provide the required spring support for the vehicleframe on the wheels 30.

As with the form of the invention shown in FIGS. 1-10, the three tandemwheel suspension shown in FIGS. l112 is self-steering in that the innerbearings 65 of the cross shafts 33 of the front and rear wheels are freeto move fore-and-aft and hence assume a self-steering angularity both inrounding curves and also in returning to the straightaway. Thisfore-and-aft freedom of the inner ends of these cross shafts 33 isprovided by the graphite impregnated and hard steel plates 90, 92 whichslide horizontally with reference to each other and are interposedbetween the frame 25 and the bearings 65 for these cross shafts 33 forthe front and rear wheels 30. Accordingly, while the center wheel 30 ofthe three at each side of the vehicle is held in a fixed axial positionwith reference to the frame 25 by its bearings and 65, the other twocross shafts 33 are free to move about the vertical axes of theirbearings 35 to inwardly converging relation to each other (in rounding acurve and in avoiding tire scuff) and to parallel relation to each otherand to the center cross shaft 33 (in returning to a straightaway andagain to avoid tire scuff).

Single wheel suspension FIGS. 13 and 14 It is apparent that theinvention can be adapted to a heavy duty vehicle having the rear end ofits frame supported by single wheels in contradistinction with thetandem two and three wheel suspensions previously described at each sideof the vehicle. Such form of the invention is illustrated in FIGS. 13and 14 from which it will be particularly noted that the same componentsare provided except that the outboard end of each compensating lever 95,instead of being connected through the shackle 96 with a companioncompensating lever, is connected directly to the frame 25. Thus theframe 25 is provided at this point with cross beams 28 above theoutboard end of the arm 32 at each side of the vehicle. Above each ofthese outboard ends a frame bracket 150 is provided which comprises sideplates 151 secured to and depending from the cross beams 28, and whichare connected at their bottom ends by a horizontal cross plate 152 onthe top of which is secured the bottom plate 109 of the upper rubberblock 108. It will be noted that this form of the invention operates inthe same manner as the other fonms, that is, upward movement of thewheel 30 causes upward move ment of the stub axle 31 and arm 32,counterclockwise rotation of the cross shaft 33 in its rubber hushedbearings 35 and (as viewed in the figures) and hence downward movementof the lever 95. This compresses the lower rubber body 108 into itsbottom compression plate or cup 113 and through the links 125 compressesthe top compression plate or cup 113 downwardly onto the top rubber body108, this latter rubber body being held against downward movement by theframe bracket 150 so that the compression of these two rubber bodiesform substantially the entire resilient resistance between the frame 25and its wheel 30.

It will be noted that this form of the invention uses the samecomponents as all of the other forms thereby not only to provide adistinct manufacturing economy through the use of a large number ofidentical parts but also to reduce the inventory of dealers throughoutthe country in stocking replacement parts for vehicles involved inwrecks.

As in the preceding description, in the following claims wheel isintended to include the ground engaging wheel means 30 supporting eachstub axle regardless of whether in the form of a single wheel or in theform of the dualtired wheel shown.

From the foregoing it will be seen that the present invention achievesthe various objects and has the advantages previously set forth and alsoprovides a wide variety of duo-wheel tandem, tri-wheel tandem and singleaxle suspensions which are principally composed of identical andinterchangeable parts.

Except for the last of the following claims the reference characters canall be found on FIGS. 1-10, but this is only for convenience in applyingthe claims and does not infer that certain of the claims are not genericto all forms illustrated.

I claim:

1. A vehicle spring suspension adapted to be interposed between avehicle frame (25) and a stub axle (31) supported by a rubber tiredwheel (30) rotatable about the axis of said stub axle (31) and having anarm (32) having one end supported by said stub axle (31) and extendinggenerally lengthwise of the line of travel of the vehicle, a horizontalcross shaft (33) journalled on said frame (25) to extend generallyparallel with the axis of said wheel (30) and fixed to the other end ofsaid arm (32), a lever operatively connected with and projectingradially relatively to said cross shaft (33) to be oscillated thereby;wherein the invention comprises a first (108) and a second (108) rubberbody, arranged to be jointly acted on in tandem in direct compressionand expanding and contracting laterally toward and from the center lineof the path of compression to provide substantially the entireresiliency in supporting said frame (25) on said wheel (30), a pair ofbacking plates (109) severally engaging the sides of said rubber bodies(108) which oppose each other, a pair of compression plates (113)severally engaging the sides of said rubber bodies (108) remote from thesides engaged by said backing plates (109), the backing plate (109) ofone rubber body (108) being operatively connected to the outboard end ofsaid lever (95) to transmit pressure therefrom compressively to said onerubber body (108), shackle linkage means (119* 130) operativelyconnecting the compression plate (113) of said one rubber body (108)with the compression plate (113) of the other rubber body (108), andmeans (95, 33, 32, 31, 30) operatively connecting the backing plate(109) of the other rubber body (108) to said vehicle frame (25 2. Avehicle spring suspension as set forth in claim 1 additionally includinga third rubber body (131) operatively interposed and yieldingly holdingin spaced relation said backing plates (109) of said first and secondrubber bodies (108).

3. A vehicle spring suspension as set forth in claim 1 wherein eachcompression plate (113) is cup-shaped with a concave face provided witha flaring periphery (115) engaging said side of its rubber body (108)remoted from the side engaged by its backing plate (109) and whereinsaid side of each rubber body remote from the side engaged by itsbacking plate (109) is of convex form with a flaring periphery (113)being shallower than the flaring periphery (111) of the convex side ofthe companion rubber body 108) whereby the initial expansion andcontraction of each rubber body (108) toward and from said center lineis to conform it to the flaring periphery (115) of its compression plate(113) 4. A vehicle spring suspension as set forth in claim 1 whereinsaid shackle linkage means (119-130) comprises shackle links on oppositesides of said rubber bodies (108), backing plates (109) and compressionplates (113), cross bars (121) severally connecting opposite ends ofsaid shacke links (125) and arranged across the sides of saidcompression plates (113) which are remote from each other, and means(119) pivotally connecting each compression plate (113) to its companioncross bar (121).

5. A vehicle spring suspension as set forth in claim 4 wherein saidpivotally connecting means (119) is in the form of a rolling socketjoint.

6. A vehicle spring suspension adapted to be interposed between avehicle frame and a stub axle (31) supported by a rubber tired wheelrotatable about the axis of said stub axle (31) and having an arm (32)having one end supported by said stub axle (31) and extending generallylengthwise of the line of travel of the vehicle, a horizontal crossshaft (33) journalled on said frame (25) to extend generally parallelwith the axis of said wheel (30) and fixed to the other end of said arm(32), a lever (95) operatively connected with and projecting radiallyrelatively to said cross shaft (33) to be oscillated thereby; whereinthe invention comprises a second rubber tired wheel (30) arranged intandem relation to said first mentioned rubber tired wheel (30) androtatable about an axis generally parallel with said axis of said stubaxle (31), a second stub axle (31) supported by said second rubber tiredwheel (30), a second arm (32) having one end supported by said secondstub axle (31) and extending generally lengthwise of the line of travelof the vehicle toward said first mentioned stub axle (31), a secondhorizontal cross shaft (33) journalled on said frame (25) to extendgenerally parallel with the axes of said wheels (30) and fixed to theother end of said second arm (32), a second lever (95) fixed to andprojecting outwardly from said second cross shaft (33) with its outboardend in vertically spaced relation to the outboard end of said firstmentioned lever (95) and shackle means (108430) including resilientmeans (108), pivotally connecting together said outboard ends of saidfirst mentioned and second levers (95), said resilient means (108)permitting yieldingly resisted movement of said outboard ends of saidfirst mentioned and second levers (95) toward each other and reacting toreturn them to a normal spaced relation provided by the shackle means(108130).

7. A vehicle spring suspension as set forth in claim 6 wherein saidresilient means (108) comprises at least one resilient rubber body(108).

8. A vehicle spring suspension as set forth in claim 6 wherein saidshackle means (108-130) comprises resilient rubber bodies (108)severally secured to the sides, remote from each other, of said outboardends of said first mentioned and second levers (95), compression plates(113) arranged against the faces of said rubber bodies (108) which areremote from each other, and shackle links (125) pivotally connectingsaid compression plates (113) together.

9. A vehicle spring suspension as set forth in claim 8 wherein saidshackle linkage means (119-130) comprises shackle links (125) onopposite sides of said rubber bodies (108) and compression plates (113),cross bars (121) severally connecting opposite ends of said shacklelinks (125) and arranged across the sides of said compression plates(113) which are remote from each other, and means (119) pivotallyconnecting each compression plate (113) to its companion cross bar(121).

10. A vehicle spring suspension as set forth in claim 9 wherein saidpivotally connecting means (119) is in the form of a rolling socketjoint.

11. A vehicle spring suspension adapted to be interposed between avehicle frame (25) and a stub axle (31) supported by a rubber tiredwheel (30) rotatable about the axis of said stub axle (31) and having anarm (32) having one end supported by said stub axle (31) and extendinggenerally lengthwise of the line of travel of the vehicle, a horizontalcross shaft (33) journalled on said frame (25) to extend generallyparallel with the axis of said wheel (30) and fixed to the other end ofsaid arm (32), a lever (95) operatively connected with and projectingradially relatively to said cross shaft (33) to be oscillated thereby,spring means (96) operatively interposed between the outboard end ofsaid lever (95) and said frame (25) and resisting upward movement ofsaid arm (32) with reference to said vehicle frame (25) to yieldinglysupport the vehicle frame 25 on said Wheel; wherein the inventioncomprises said horizontal cross shaft (33) being so journalled on saidframe (25) by an outer resilient rubber bushing (35) held in compressiverelation with the outboard end of said cross shaft (33) by a bearinghousing (38, 39) and arranged to be at least in part positionedoutwardly beyond the plane of the inner circular face of the tire ofsaid rubber tired wheel (30), and an inner resilient rubber bushing (65)held in compressive relation with the inboard end of said cross shaft(33) by a bearing housing (68, 69) arranged adjacent the longitudinalcenter line of the frame (25).

12. A vehicle spring suspension as set forth in claim 6 wherein each ofsaid horizontal cross shafts (33) is so journalled on said frame by anouter bearing (35) arranged to be at least in part positioned outwardlybeyond the plane of the inner circular face of the tire of itscorresponding rubber tired wheel (30), and an inner bearing (65)arranged adjacent the longitudinal center line of the frame (25).

13. A vehicle spring suspension as set forth in claim 12 wherein each ofsaid bearings (35, 65) is in the form of a resilient rubber bushing (36,66) held in compressive relation with the corresponding end of saidcross shaft (33) by a bearing housing (38, 39, 68, 69).

14. A vehicle spring suspension as set forth in claim 12 additionallyincluding means (90, 92) permitting movement of one of said innerbearings (65) in a generally horizontal direction lengthwise of the lineof travel of the vehicle to render said tandem rubber tired wheels (30)self-steering in rounding curves.

15. A vehicle spring suspension as set forth in claim 12 wherein each ofsaid outer bearings (35) is in the form of a resilient rubber bushing(36) held in compressive relation with the outer end of thecorresponding cross shaft (33) by a bearing housing (38, 39) and whereinthe spring suspension additionally includes means (90, 92) permittingmovement of one of said inner bearings (65) in a generally horizontaldirection lengthwise of the line of travel of the vehicle to render saidtandem rubber tired wheels (30) self-steering in rounding curves.

16. A vehicle spring suspension adapted to be interposed between avehicle frame (25) and a stub axle (31) supported by a rubber tiredwheel (30) rotatable about the axis of said stub axle (31) and having anarm (32) having one end supported by said stub axle (31) and extendinggenerally lengthwise of the line of travel of the vehicle, a horizontalcross shaft (33) journalled on said frame (25) to extend generallyparallel with the axis of said wheel (30) and fixed to the other end ofsaid arm (32), a lever (95) operatively connected with and projectingradially relatively to said cross shaft (33) to be oscillated thereby,spring means (96) operatively interposed between the outboard end ofsaid lever (95) and said frame (25) and resisting upward movement ofsaid arm (32) with reference to said vehicle frame (25) to yieldinglysupport the vehicle frame (25) on said wheel; wherein the inventioncomprises said spring means (96) operatively interposed between theoutboard end of said lever (95) and said frame (25) additionallyincluding second rubber'tired wheel (30) arranged in tandem relation tosaid first rubber tired wheel (30) and rotatable about an axis generallyparallel with said axis of said stub axle (31), a second stub axle (31)supported by said second rubber tired wheel (30), a second arm (32)having one end supported by said second stub axle (31) and extendinggenerally lengthwise of the line of travel of the vehicle toward saidfirst mentioned stub axle (31), a second horizontal cross shaft (33)journalled on said frame (25) to extend generally parallel with the axesof said wheels (30) and fixed to the other end of said second arm (32),a second lever (95) fixed to and projecting outwardly from said secondcross shaft (33) toward said first mentioned lever, a third rubber tiredwheel (30) arranged in tandem 13 between said first mentioned and secondrubber tired wheels (30) and rotatable about an axis generally parallelwith said axis of said first mentioned stub axle (31) a third stub axle(31) supported by said third rubber tired wheel (30), a third arm (32)having one end supported by said third stub axle (31) and extendinggenerally lengthwise of the line of travel of the vehicle, a thirdhorizontal cross shaft (33) journalled on said frame (25) to extendgenerally parallel with the axes of said Wheels (30) and fixed to theother end of said third arm (32), a double ended lever (134) fixed atits center to said third cross shaft (33) and having one end (135)projecting generally along the line of travel of the vehicle to aposition in vertically spaced relation to the outboard end of said firstmentioned lever (95), a first shackle means (108130) including resilientmeans (108) connecting together the outboard end of said first mentionedlever (95) with said one end (135) of said double ended lever (136),said double ended lever having another end (136) projecting generallyalong the line of 20 travel of the vehicle to a position in verticallyspaced relation to the outboard end of said second lever (95),

and a second shackle means (108-130) including resilient means (108)connecting together the outboard end of said second lever (95) with saidanother end (136) of said double ended lever 134, the resilient means(108) of each of said first and second shackle means (108-130)permitting yieldingly resisted movement of said outboard ends of saidfirst mentioned and second levers (95) toward their respective one (135)and another (136) ends of said double ended lever (134) and reacting toreturn them to a normal spaced relation provided by said shackle means(108130).

References Cited UNITED STATES PATENTS 2,920,903 1/1960 Locker 280104.5

3,135,508 6/1964 Boys 267-21 2,202,615 5/1940 Barenyi 267-21 FOREIGNPATENTS 1,229,793 3/ 1960 France.

PHILIP GOODMAN, Primary Examiner.

